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A large-Schmidt-number asymptotic approximation procedure is employed to derive an equation which represents mass transfer accompanied by a first-order chemical reaction for liquids in fully developed turbulent flow in a circular tube. However, since the concentration boundary layer is very thin, the results obtained should also apply to the parallel-plate and concentric-annulus geometries when proper scaling is employed. A modified Van Driest formula for the eddy diffusivity

Froment, G. F., Ed.; Elsevier: Amsterdam, 1980 p 91. Mlron, S.; Lee, R. J. Dev. 1062, 7, 102. 1964. Process Des. Dev. 1066, 5, 193. Ozawa, Y.; Blschoff, K. Ind. fng. Chem. Process Des. Dev. 1068r, 7 , 72. Ozawa, Y.; Blschoff, K. Ind. Eng. Chem. Process Des. Dev. 1068b, 7, 67. Pachovsky, R. A.; Best, D.; Wojciechowskl, B. W. Ind. fng. Chem. Process Poutsma, M. L.A UNIFAC groupinteraction parameter table especially suited for prediction of liquid-liquid equilibria at temperatures between 10 and 40 O C has been developed. A total of 512 binary parameters representing the interactions between 32 different groups have been determined on the basis of approximately 100 binary and 300 ternary liquid-liquid

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The heaviest elements to have been chemically characterized are seaborgium (element 106), bohrium (element 107) and hassium (element 108). All three behave according to their respective positions in groups 6, 7 and 8 of the periodic table, which arranges elements according to their outermost electrons and hence their chemical properties. However, the chemical characterization results are not trivial: relativistic effects on the electronic structure of the heaviest elements can strongly influence chemical properties. The next heavy element targeted for chemical characterization is element 112; its closed-shell electronic structure with a filled outer s orbital suggests that it may be particularly susceptible to strong deviations from the chemical property trends expected within group 12. Indeed, first experiments concluded that element 112 does not behave like its lighter homologue mercury. However, the production and identification methods used cast doubt on the validity of this result. Here we report a more reliable chemical characterization of element 112, involving the production of two atoms of (283)112 through the alpha decay of the short-lived (287)114 (which itself forms in the nuclear fusion reaction of 48Ca with 242Pu) and the adsorption of the two atoms on a gold surface. By directly comparing the adsorption characteristics of (283)112 to that of mercury and the noble gas radon, we find that element 112 is very volatile and, unlike radon, reveals a metallic interaction with the gold surface. These adsorption characteristics establish element 112 as a typical element of group 12, and its successful production unambiguously establishes the approach to the island of stability of superheavy elements through 48Ca-induced nuclear fusion reactions with actinides.

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